Chilean paleontologists presented their findings on a dinosaur discovered three years ago in Patagonia with an extremely unique tail that has perplexed researchers on Wednesday.
When was the remnants found
The remnants of the Stegouros elengassen were discovered during digs in 2018 at Cerro Guido, a site noted for containing numerous fossils, by a team that initially thought they were dealing with an already-known dinosaur species until they examined its tail.
What does the paleontologists say
“That was the main surprise,” one of the paleontologists, Alexander Vargas, remarked. “This structure is absolutely amazing.”
During a presentation of the discovery at the University of Chile, the researcher added, “The tail was covered with seven pairs of osteoderms … producing a weapon absolutely different from anything we know in any dinosaur.”
The osteoderms, which are bony plaque structures found in the skin’s dermal layers, were aligned on either side of the tail, giving it the appearance of a large fern.
Paleontologists have unearthed 80 percent of the dinosaur’s skeleton, putting its age between 71 and 74.9 million years ago. It was about seven feet long, weighed 150 kilos (330 pounds), and was a herbivore.
What does the animal represent
The animal could represent a previously unknown lineage of armoured dinosaurs never seen in the southern hemisphere but already identified in the northern section of the continent, according to the scientists, who published their findings in the journal Nature.
“We don’t know why (the tail) evolved. We do know that within armored dinosaur groups there seems to be a tendency to independently develop different osteoderm-based defense mechanisms” Sergio Soto, another team member, said.
Cerro Guido area
The Cerro Guido area, located 15 kilometres south of Santiago in the Las Chinas valley, runs for 3,000 kilometres (1,800 miles). Numerous fossils can be found in various rock outcrops.
Scientists were able to deduce from the findings that modern-day America and Antarctica were formerly close to each other millions of years ago.
“There is strong evidence that there is a biogeographic link with other parts of the planet,” Soto said. “In this case Antarctica and Australia, because we have two armored dinosaurs there closely related” to the Stegouros, said Soto.